Follow the directions on the box for the pasta. Make sure you cook them al dente.
Saute onions, mushrooms and garlic in 1 Tbsp of the butter until tender.
Remove the onions, mushrooms and garlic and set them aside until later.
In the same pan, cook the chicken, stirring frequently.Remove the chicken and it aside until later. To the same pan, add 2 Tbsp butter and melt over a low-medium heat.
Sprinkle the flour over the butter and stir to make a roux. Slowly add in the wine, water and heavy cream, stirring constantly.
Cook over a medium-high heat until thickened Stirring often to keep it from sticking to the bottom of the pan.
Add the parsley and let simmer for a few minutes.
Add the chicken, mushrooms, garlic and onions back in and simmer for 2 more minutes.
Pour over the pasta and serve with Parmesan cheese.